Greg Hughes, a spokesman for NBC Sports, says the company "is aware of the situation" and has been in contact with Michaels. Hughes had no further comment.

A call Sunday by The Associated Press to Michaels' agent was not immediately returned.

An Emmy Award winner and broadcaster on "Sunday Night Football," the 68-year-old Michaels spent nearly three decades at ABC Sports before moving to NBC in the 2007.

Michaels worked NFL games and other sports for ABC, and called "Monday Night Football" for nearly 20 years. He also is known for his call of the U.S.-Soviet Union "Miracle on Ice" game at the 1980 Winter Olympics.

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